Surgical microscopes for ophthalmic surgery are known from the prior art, for example from DE 10300925 A1. Such surgical microscopes are usually embodied in such a way that they generate a stereoscopic image of the eye such that the surgeon obtains a spatial impression of the eye to be operated.
In ophthalmic surgery, it is important for the surgeon to know the refractive state of the eye as present at the time of the intervention. By way of example, in the case of cataract operations, the refractive properties are required if the orientation of a toric lens needs to be set. Another problem in the case of cataract operation consists of an intraocular lens being inserted, the values of which were established on the basis of measurements which were carried out prior to the surgical intervention. However, such measurements may be erroneous due to the lens opacification caused by the cataract. Therefore, it is desirable to check the refractive properties of the eye once more prior to the insertion of the intraocular lens but after the removal of the eye lens, that is, on the aphakic eye, so that the lens selection can be corrected where necessary. It is also of interest to check the refractive values of the eye directly after the completion of the operation.
The prior art has disclosed intraoperative refraction measurements, which establish the wavefront emerging from the eye via parallel or time-sequential measurement systems and determine the refractive properties of the eye therefrom. However, these measurement methods are very complicated and require that additional, complex beam paths are coupled into the eye, as a result of which the outlay required for the surgical microscope increases.
The prior art has disclosed a method referred to as “phase retrieval”, which allows conclusions to be drawn about a transfer quality of an optical system by way of specific measurements.